Rack. A straight body, having on it, (1) teeth corresponding to the teeth in the wheel that drives it or that it drives; (2) notches to engage a pawl or ratchet.
Rack-feed. A feed motor in which the work-table has a rack driven by a gear-wheel.
Rake. The inclination of the front face of a cutting tool to the body of the steel of which it is made.
Ratchet. A pawl or tongue one end of which engages in notches in a rack or wheel.
Ratchet-brace. A hand-drilling device, in which a lever carries a pawl that engages with a ratchet-wheel, which drives the drill.
Rat-tail file. A taper round file of small diameter or less than one-fourth of an inch.
Reamer, rymer, or rimer. A tool for smoothing and enlarging bores or holes.
Recut-file. A file whose original teeth have been ground off and new teeth have been cut.
Red-marking. A mixture of Venetian red and common oil, used to put on a piece of work when trying its fit, and serving to denote the fit.
Return-cam. A secondary cam used to move a piece back, after the main cam has moved it forward.